大気熱エンジンによる極方向熱輸送
Leon Barry1, George C Craig, John Thuburn
1Department of Meteorology, University of Reading, Earley Gats, Whiteknights, UK.
Nature
|February 15, 2002
まとめ
中緯度の嵐は,熱を赤道から極地まで運ぶ. 新しい熱エンジン理論は,嵐の強度と渦の速度を説明し,気候モデルと嵐の予測を改善します.
科学分野:
- 大気科学 大気科学
- 気候のダイナミクス
- 気象学 気象学 気象学
背景:
- 地平線から極点への大気熱輸送は,主に中緯度の嵐によって引き起こされます.
- 極方向の熱伝送に関する既存の理論は,渦のスケールに関するコンセンサスを欠いている.
- 中緯度の嵐は,地球の気候の調節に極めて重要です.
研究 の 目的:
- 中緯度の嵐による大気中の熱伝送に関する新しい理論的枠組みを開発する.
- 渦巻き運動エネルギー生成のための新しい熱エンジンモデルを提案する.
- 気候シミュレーションを使用して,新しいおよび既存の渦のスケールを検証します.
主な方法:
- 渦の性質を調査するために数値気候シミュレーションが採用されました.
- 強制力と境界条件は,渦の特徴を変化させるために変更されました.
- 提案された速度および長さのスケールは,シミュレーションの結果に対してテストされました.
主要な成果:
- この研究は,渦巻き運動エネルギー生成のための新しい速度スケールを導入しています.
- エディの速度は,提案された新しいスケールと相関することが判明しました.
- エディのサイズは一貫して確立されたレインベータスケールに従った.
結論:
- 熱エンジン理論は,大気中の熱伝送に関する新しい視点を提供します.
- この発見は,中緯度の嵐の強度を推定するためのより単純な方法を提供します.
- この研究は,根本的な気候プロセスと嵐のダイナミクスの理解を前進させます.
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